DE102019112756A1 - Device for force absorption, transmission and damping of mechanical vibrations - Google Patents

Abstract

The invention relates to a device for absorbing force, transmitting and damping mechanical vibrations, comprising at least two outer, interconnected components made of coherent materials (10, 14, 18, 20, 22, 25) which together form a closed cavity that is at least partially with damping Material (30) is filled, which encloses at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) in the region of its smallest thickness, and in the region of its maximum thickness with at least one of the two outer Components (10, 14, 18, 20, 22, 25) is firmly connected. Furthermore, the invention relates to a device for absorbing force, transmitting and damping mechanical vibrations in a bearing.

Description

The present invention relates to a device for establishing contact, forwarding and damping mechanical vibrations.

The principle of acoustic black holes describes a plate whose thickness h increases with a continuously increasing profile function such as h = ε · x ⁿ or h = y · sin ^m (x) along a distance x, where n, m ≥1. A minimum edge thickness h ₀ that can just be produced cannot be fallen below. The thickness of the plate only increases up to a certain height; in the case of a milling production of the acoustic black hole, the initial thickness of the sheet metal d. Due to the thickness dependency of the propagation speed of flexural waves, the design means that with small thicknesses this continues to decrease, and with a hypothetical h ₀ = 0 mm the value 0 achieved, with simultaneously large amplitudes. This effect has already been demonstrated by MA Mironov ("Propagation of a flexural wave in a plate whose thickness decreases smoothly to zero in a finite interval"; Soviet Physics - Acoustics; Vol. 34 (1988); pp. 318-319) disclosed, where the term acoustic black hole has not yet been used. VV Krylov, ("Acoustic, black holes' for flexural waves and their potential applications"; Proceedings of the Institute of Acoustics Spring Conference; Salford, UK, 25-27 March 2002) referred to Mironov's publication when he first used this term in 2002 in a publication devoted to the practical applications of Mironov's ideal structure in which the bending waves of a vibrating solid surface are completely absorbed without reflection. The problem here is that a wedge thickness of exactly 0 mm cannot be represented in practice or the inevitability of a rounding or a shoulder at the start of the profile and thus the occurrence of reflections on every real production of Mironov's mathematically described profile. In another publication on the subject, Krylow and Tilman show ("Acoustic 'black holes' for flexural waves as effective vibration dampers"; Journal of Sound and Vibration; Vol. 274 (2004); pp. 605-619) a possibility to reduce the reflection coefficient of the ABH at a real break-off edge and thus the practically demonstrable improvement of the absorption behavior by applying a thin, dampening plastic layer in the area of the sharp edge of the acoustic black hole. Two-dimensional acoustic black holes are geometries in which the change in thickness is not only described along an axis in the plane of the plate, but, as disclosed in the prior art, starts from a center point on the plate, from which the plate thickness increases in a circular manner outward . V. Denis ("Vibration damping in beams using the acoustic black hole effect; PhD thesis, Universite du Maine; 2014) examined in particular the effect of irregularities on the sharp edge and came to the conclusion that these have a positive effect on the damping behavior within the meaning of the invention. Furthermore described W. Jeon ("Vibration damping using a spiral acoustic black hole"; Internoise 2016 conference proceedings; Hamburg 2016; pp. 2387-2390) spiral-shaped acoustic black holes with a length of up to 720 mm, and demonstrated the improvement in the damping effect of the acoustic black hole with increasing wedge length. The result is a high mode density with a high modal overlap, which V. Denis recognized as the cause of the effectiveness of ABH in a wide frequency range. EP Bowyer et al. ("Acoustic black hole manufacturing for practical applications and the effect of geometrical and materials imperfections"; Internoise 2016 conference proceedings; Hamburg, 2016; pp. 2411-2421) disclosed the problems of generating the profiles by milling, as it was previously practiced for research purposes, and proposed the casting process, forging, and working with material composites from thin layers and rapid prototyping as future production methods. In this work an acoustic black hole made of a plastic composite material is examined for the first time and the self-damping of this material is proven to be advantageous, making the use of a damping film on the sharp ABH edge unnecessary.

US 2013/0071251 A1 discloses a vibration-damping fluid dynamic application, such as a turbine blade, a propeller blade or a wing, which tapers in a wedge shape to the leading or trailing edge. In the DE 10 2015 100 442 A1 a structure with acoustic black holes is shown, in which an electromechanical transducer is coupled to the point (s) of smallest thickness, which not only amplifies the damping, but can also be used as an energy harvester, and in connection with a control loop the system can add active cushioning. In the DE 10 2016 116 554 B3 the application of a geometry from acoustic black holes in a passenger aircraft is shown. Due to the decrease in the thickness of the interior lining of the passenger cabin to seal the window complex, an easy-to-implement, existing construction that only changes slightly and is invisible in the specific application is proposed to use the acoustic black hole effect to reduce noise in the passenger cabin. In the CN 106 023 979 A an acoustic black hole with a spring-mass system at the point (s) of the smallest thickness is proposed, which increases the effect of the acoustic black hole in the area of its natural resonance, and at the same time the effective frequency range of the acoustic black hole restricts. In the US 2018/0335406 A1 a metrological application in the field of structural health monitoring is presented. Here the property of the thin edge of an acoustic black hole to amplify the amplitude of an incoming vibration is used to detect vibrations normal to a plate plane with a sensor and to separate them from longitudinal vibrations in the plane. Such a recording of transverse vibrations through a structure of acoustic black holes is also made useful in the present document.
The applications of acoustic black holes known in the prior art, however, are not suitable for absorbing and transmitting forces, because the thin edges of the acoustic black holes would tear even with small forces and thus occur with crack propagation and the resulting component damage.

Die Randdicke h₀ bei x₀ sollte so klein wie möglich sein. Das heißt durch Wahl des Fertigungsverfahrens und die spezifische Ausführung desselben erfolgt eine Annäherung der Randdicke möglichst nahe an 0 mm, wobei Unregelmäßigkeiten und sogar kleine Einrisse am Rand in Kauf genommen werden können, welche sich positiv auf den Dämpfungseffekt des Akustischen Schwarzen Lochs auswirken. Ist verfahrensbedingt eine bestimmte Minimaldicke gegeben, so kann die entsprechende Kante mit der Höhe h₀ verlängert ausgeführt und/oder zusätzlich flach angeschliffen werden, wobei die Ausbildung von Unregelmäßigkeiten der Kante ebenfalls erwünscht ist, und eine Unstetigkeit der ersten Ableitung der Profilfunktion des Akustischen Schwarzen Lochs in Kauf genommen werden darf.
Die folgend beschriebenen einfachen Akustischen Schwarzen Löcher können als Spezialfälle schalenförmiger 3-dimensionaler Akustischer Schwarzer Löcher betrachtet werden, und zwar als ebene Ausprägungen rotationssymetrischer Akustischer Schwarzer Löcher bei unendlichem Radius und abschnittsweiser Ausprägung (1-dimensionale Akustische Schwarze Löcher), sowie als ebene Ausprägungen rotationssymetrischer Akustischer Schwarzer Löcher bei endlichem Radius und vollständiger Ausprägung (2-dimensionale Akustische Schwarze Löcher). In diesen ebenen Sonderfällen erfolgt die Dickenabnahme hin zum Rand entlang den in der Ebene liegenden Normalen lotrecht zur Umfangskoordinate u. Weiterhin sind partielle Ausprägungen entlang nur einer geraden Kante möglich, beispielsweise eine kammförmige Gestaltung, auch mit unterschiedlich langen Zungen wie beim Tonkamm einer Walzen-Spieldose. Die allseitige Ausdehnung mit langem Steg minimaler Dicke wie bei kreisförmigen Akustischen Schwarzen Löchern hingegen ist als dämpfungsfördernd anzusehen. Eine weitere Gestaltungsmöglichkeit ebener Akustischer Schwarzer Löcher ist die stetige Veränderung von x₀, ε oder n in der obigen Gleichung entlang der Umfangskoordinate u. So kann zum Beispiel durch eine stetige Abnahme von ε bei gleichbleibender Randdicke h₀, Maximaldicke d und Anstiegspotenz n die Länge des Akustischen Schwarzen Lochs l_ABH entlang der Umfangskoordinate u erhöht werden. Durch eine solche Variabilität der Gleichungsparameter lässt sich zum Beispiel der oben erwähnte Beschnitt der Akustischen Schwarzen Löcher so darstellen, dass auch die Abschnittkanten Akustische Schwarze Löcher-Charakter haben, und so die dämpfende Wirkung, wenn auch bei höheren Frequenzen, verbessert wird. Weiterhin denkbar sind gekrümmte, das heißt schalenförmige, dreidimensionale, oft unsymmetrische Akustische Schwarze Löcher. Bei Akustischen Schwarzen Löchern aus einem biegbaren Material ist es möglich, die gekrümmte Geometrie durch Umformen eines ebenen Akustischen Schwarzen Lochs zu erzeugen. Bei einer Schale in Form einer halben Ölwanne, muss hingegen die Akustische Schwarze Loch-Koordinate x_i, entlang derer die Dicke des Materials des Akustischen Schwarzen Lochs zunimmt, nicht gerade, sondern kurvenförmig im 3-dimensionalen Raum verlaufend betrachtet werden. Sie schneidet sich nirgends mit den benachbarten ebenfalls kurvenförmigen x-Koordinaten x_i-1 und x_i+1, welche an differentiell nahe gelegenen Ausgangspunkten der (ebenfalls kurvenförmigen, 2- oder 3-dimensionalen) Umfangskoordinate beginnen und sich in Länge und räumlichem Verlauf differentiell von ihr unterscheiden können. Somit haben schalenförmige Akustische Schwarze Löcher in den meisten möglichen Fällen keine einheitliche Akustische Schwarze Loch-Länge entlang der verschiedenen gekrümmten Koordinaten, weisen somit in dem dünnen, dissipierenden Randbereich entweder unterschiedliche h₀ auf, oder bei annähernd konstanten h₀ über den Bereich stetig variierende ε oder n.
Die erfindungsgemäße Vorrichtung dient der passiven Schwingungsdämpfung und der akustischen Beruhigung insbesondere Geräusche abstrahlender, flächenartiger technischer Gebilde sowie kraftleitenden Maschinenlagern, wobei die erfindungsspezifische Vorrichtung einen Einsatz unter kritischen Bedingungen wie wechselnder starker Belastungen und hohen Temperaturen ermöglicht, wobei eine schädigende Kraft-Einwirkung auf insbesondere dünne, besonders schädigungsanfällige Bereiche des mindestens einen Akustischen Schwarzen Lochs vermieden wird.
Weiterhin vorteilhaft ist, dass die erfindungsgemäße Vorrichtung ohne nennenswerte kraftleitende Funktion allein der Verringerung der Amplituden hörakustisch relevanter Schwingungen an schallabstrahlenden Oberflächen unterschiedlicher, nahezu beliebiger Formen dienen kann. Auch kann die erfindungsgemäße Vorrichtung als passiv schwingungsdämpfendem (Maschinen-)Lager zur Kraftleitung bei gleichzeitig effektiver Körperschalldämpfung Anwendung finden. Die Eckfrequenz dieses passiv wirkenden mechanischen Tiefpasses lässt sich durch die Wahl der Länge des Akustischen Schwarzen Loches l_ABH festlegen. Diese wird umso größer ausfallen müssen, desto kleiner die gewünschte Eckfrequenz ist.
Die erfindungsgemäße Vorrichtung bietet im Wesentlichen den Vorteil, durch eine Fokussierung und Verstärkung hörakustisch relevanter Schwingungen in einem konstruktiv festgelegten Bereich durch die Anwendung plattenförmiger, dünner Akustischer Schwarzer Löcher eine Beruhigung der übrigen Vorrichtung zu bewirken und im genannten Bereich die Dämpfungseffizienz zu erhöhen. Somit wird mit geringem Bauteilaufwand das Material besonders schallmindernd gestaltet.
In einer weiteren bevorzugten Ausführungsform der erfindungsgemäßen Vorrichtung, umfasst die Vorrichtung weiterhin einen Rahmen 115, der zusammen mit den äußeren Bauteilen 10, 14, 15, 18, 20, 22, 25 den geschlossenen Hohlraum bildet.There are various devices with self-damping properties in the passenger car sector. In the body area describes the EP 0 245 636 B1 a soundproofing plate with a carrier layer made of synthetic fiber fleece, a sound-absorbing layer made of plastic foam and an optionally watertight cover layer. This sound-absorbing plate can be attached to the sound-incident side (for example the engine hood) and thus contribute to its calming. Furthermore, the DE 10 2012 022 935 A1 a vibration damping structure for the vehicle floor panel, in particular of a car, which dampens longitudinal waves by means of arched, trapezoidal sheet metal sections and is an integral part of the floor panel. A self-damping concept is also in the laid-open specification DE 10 2006 004 432 A1 disclosed. The disclosed oil pan is distinguished by a thin, damping foam rubber layer attached to the outside, which carries a closed barrier layer made of urethane. The foam rubber and barrier layers together represent a mass-damper-spring system which, when the oil pan vibrates, can increasingly dissipate vibration energy in its own resonance frequency range.
The invention is therefore based on the object of providing a device which is used for passive vibration damping and acoustic calming, in particular flat technical structures which emit noises, as well as force and vibration-conducting bearings, in particular for machines.
Furthermore, it is an object of the present invention to provide a device which enables use under critical conditions such as alternating high loads and high temperatures, with a damaging force being avoided.
Furthermore, it is an object of the present invention to provide a device in which vibration energy is converted into heat by dissipation, without excessive tensile or bending loads acting on the thin edges of the acoustic black holes, which cause cracks, material breaks and would lead to a loss of functionality.
The object of the invention is achieved by providing a device for absorbing and transmitting static and low-frequency effects and for conducting higher-frequency components of the effect into a load-free area where they are effectively damped, which device has the features of the main claim. Advantageous further developments of the device according to the invention are presented in the dependent claims.
The subject of the invention is a device for absorbing and transmitting mechanical vibrations, the at least two outer, interconnected components made of coherent materials 10 , 14th , 15th , 18th , 20th , 22nd , 25th , which together form a closed cavity which is at least partially filled with damping material, which is at least one acoustic black hole 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 encloses in the region of its smallest thickness, and that in the region of its maximum thickness with at least one of the two outer components 10 , 14th , 15th , 18th , 20th , 22nd , 25th is firmly connected.
In the context of the present invention, the at least two outer, interconnected components made of coherent materials are also called cladding parts. In the context of the present invention, the at least two outer components are selected from a cover plate and a base plate or a main plate and a support plate or from an inner shell or outer shell.
The advantage of the device according to the invention is that it is particularly suitable for applications in which a plate-shaped or shell-shaped component absorbs vibrations and transmits, possibly amplifies and emits them, without this being of technical or other benefit or desired , be it as airborne or liquid-borne noise, or as mechanical vibration of adjacent parts (structure-borne noise).
It is also advantageous that the space-saving integrated damping material, also referred to as damping material in the context of the present invention, makes the propagation of the vibration within the plate more difficult due to friction processes occurring inside the material and thus reduces the sound radiation of the cladding parts.
The at least one acoustic black hole, in particular the critical thin area of the acoustic black hole, is preferably enclosed by the damping material, as a result of which this area is protected, and a critical area Force introduction in these areas can be excluded. The device according to the invention is therefore also suitable for the representation of bearings and is suitable for damping vibrations directly at the point where the force is introduced. This also prevents this thin edge area from being in direct contact with the outer components.
According to the present invention, the acoustic black hole can have various shapes as long as it is plate-shaped or bowl-shaped. The at least one acoustic black hole has, starting from its smallest edge thickness h _{0 that can be} achieved in terms of manufacturing technology, along at least one direction, a steady increase in the plate thickness normal to the surface. This follows a continuous profile function with a slight rise, for example h = ε · x ⁿ for $x_0\le x\le {\left(\frac{d}{\epsilon }\right)}^{\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$n$}\right.}\left(n\ge 1\right).$

The edge thickness h ₀ at x ₀ should be as small as possible. This means that through the choice of the manufacturing process and the specific execution of the same, the edge thickness is brought as close as possible to 0 mm, whereby irregularities and even small tears at the edge can be accepted, which have a positive effect on the damping effect of the acoustic black hole. If a certain minimum thickness is given due to the process, the corresponding edge with the height h _{0 can be} extended and / or additionally ground flat, whereby the formation of irregularities of the edge is also desired, and a discontinuity of the first derivative of the profile function of the acoustic black hole may be accepted.
The simple acoustic black holes described below can be viewed as special cases of shell-shaped 3-dimensional acoustic black holes, namely as flat manifestations of rotationally symmetrical acoustic black holes with an infinite radius and in sections (1-dimensional acoustic black holes), and as flat manifestations of rotationally symmetrical acoustics Black holes with a finite radius and complete expression (2-dimensional acoustic black holes). In these flat special cases, the decrease in thickness takes place towards the edge along the normal lying in the plane perpendicular to the circumferential coordinate u. Furthermore, partial designs along just one straight edge are possible, for example a comb-shaped design, even with tongues of different lengths, such as the clay comb of a drum music box. The all-round expansion with a long web of minimal thickness, as in the case of circular acoustic black holes, on the other hand, is to be regarded as promoting attenuation. Another design option for flat acoustic black holes is the constant change of x ₀ , ε or n in the above equation along the circumferential coordinate u. For example, the length of the acoustic black hole l _ABH along the circumferential coordinate u can be increased by a steady decrease in ε with constant edge thickness h ₀ , maximum thickness d and increase potential n. Such a variability of the equation parameters allows, for example, the above-mentioned trimming of the acoustic black holes to be represented in such a way that the section edges also have the character of acoustic black holes, and so the damping effect is improved, albeit at higher frequencies. Curved, that is, shell-shaped, three-dimensional, often asymmetrical acoustic black holes are also conceivable. In the case of acoustic black holes made of a flexible material, it is possible to create the curved geometry by reshaping a flat acoustic black hole. In the case of a shell in the form of half an oil pan, on the other hand, the acoustic black hole coordinate x _i , along which the thickness of the material of the acoustic black hole increases, does not have to be viewed straight, but curved in the 3-dimensional space. It does not intersect anywhere with the neighboring, also curved, x-coordinates x _i-1 and x _{i + 1} , which start at differentially close starting points of the (also curved, 2 or 3-dimensional) circumferential coordinates and vary in length and spatial progression can distinguish from her. Thus, in most possible cases, shell-shaped acoustic black holes do not have a uniform acoustic black hole length along the various curved coordinates, so they either have different h ₀ in the thin, dissipating edge area, or ε that varies continuously over the area with approximately constant h ₀ or n.
The device according to the invention is used for passive vibration damping and acoustic calming, in particular surface-like technical structures that emit noises and force-conducting machine bearings, the device-specific device enabling use under critical conditions such as changing heavy loads and high temperatures, with a damaging force acting on particularly thin, areas of the at least one acoustic black hole that are particularly prone to damage are avoided.
It is also advantageous that the device according to the invention, without any significant force-conducting function, can serve solely to reduce the amplitudes of acoustically relevant vibrations on sound-emitting surfaces of different, almost arbitrary shapes. The device according to the invention can also be used as a passively vibration-damping (machine) bearing for power transmission with, at the same time, effective structure-borne noise damping. The corner frequency of this passive mechanical low-pass filter can be determined by the Choice of the length of the acoustic black hole l _{Define ABH} . This will have to be greater, the lower the desired corner frequency is.
The device according to the invention essentially offers the advantage of calming the rest of the device by focusing and amplifying acoustically relevant vibrations in a structurally defined area by using plate-shaped, thin acoustic black holes and increasing the damping efficiency in the area mentioned. The material is thus designed to be particularly noise-reducing with little component effort.
In a further preferred embodiment of the device according to the invention, the device further comprises a frame 115 that together with the external components 10 , 14th , 15th , 18th , 20th , 22nd , 25th forms the closed cavity.

According to a preferred embodiment of the device according to the invention, the at least two outer components are 10 , 14th , 15th , 18th , 20th , 22nd , 25th Sheet metal, plate, or shell-shaped.
At least one of the outer components preferably fulfills the function of absorbing and transmitting forces.
Furthermore, a device according to the invention is preferred in which the coherent material is selected from the group consisting of metal, plastic and composite material.
In addition, a device according to the invention is preferred in which the damping material 30th has a loss factor of η> 0.05.
The damping material is preferably selected from the group consisting of plastic foams, fine and microfibers, natural fibers, felts, air cushion films and granules.
For the purposes of the present invention, the plastic foams can be polyethylene, polyurethane, polyethersulfone or polyethylene terephthalate.
Furthermore, for the purposes of the present invention, the granules can consist of plastic, airgel or perlite.
For the purposes of the present invention, the fine or microfibers are based on natural fibers, plastics, silicate, carbon, glass or stone.
These materials are already suitable for the damping of structure-borne sound or the absorption and dissipation of air-borne sound, and this effect is enhanced by the combination with the at least one acoustic black hole. Depending on the application, different damping materials can be used. For applications that require very high heat resistance (e.g. hot and exhaust systems), for example, glass, silicate or stone fibers are suitable dampening and insulating materials that can withstand temperatures of over 1000 ° C. For applications at normal temperatures, however, fine-pored, elastic plastic foams are sufficient. With the exception of the storage structures that are partly open when exposed to stress, all other integrated acoustic black holes are also suitable for loose materials such as granulate fillings. If these should only partially fill the space in which the acoustic black holes protrude, then these fillings must, for example, with plastic foams like the supports 90 ( 90 ' , 90 " , 90 "' ) are limited. In the case of cohesive damping materials, adhesive bonding can also be used for local fixation with only partial filling of the cavity if the application temperatures are in the operating temperature range of the adhesive. Another possibility are rubber-like materials that can be introduced into the structure in liquid form and harden there. It should be noted that "overdamping" the edges of the at least one acoustic black hole can lead to a reduction in the vibration-dissipating effect.

The damping materials can be introduced into the device according to the invention in layers as coherent as well as incoherent damping materials. This offers itself in such a way that the damping lower, upper and, if necessary, intermediate layers can be introduced alternately with acoustic black holes that surround them. This is advantageous, if not essential, for a damage-free installation of the acoustic black holes.

Furthermore, a device according to the invention is preferred in which the at least one acoustic black hole 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 has a geometry which, starting from an inner surface, decreases in a radial fashion to all edges up to the minimum thickness achievable in terms of production technology.

For the purposes of the present invention, the edges are the outer boundary of the acoustic black hole in relation to the surroundings at which it has the edge thickness h ₀ . The advantage of this embodiment is that it can have an improved damping effect through the application of vibrations to a larger edge surface, in particular compared to acoustic black holes that decrease in thickness only towards one edge. It resembles the cymbal of a drum kit and favors modal vibrations with a high mode density, or even chaotic vibrations, both of which are beneficial for dissipation.

In addition, a device according to the invention is preferred in which the at least one acoustic black hole ( 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 ) over the circumferential coordinate different, continuously or discontinuously changing Coefficients of the geometry of the at least one acoustic black hole ( 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 ) assumes the specified profile function.

In the context of the present invention, the profile function is a function that is unique in the mathematical sense, which corresponds to a straight or curved coordinate x measured perpendicularly on each value from x ₀ > 0 mm to x _u = x ₀ + 1 _ABH (in mm) Material thickness h (x), which increases steadily from an edge thickness ho at x ₀ and reaches thickness d at x _u , the space between the coordinate x and h (x) being filled with a solid material according to the invention. The acoustic black hole in the sense of the invention is then the coherent area of the solid material, which is designed in such a way that it is defined by different coordinates x _{i that} do not intersect in the area and h _i (x _i ) that also do not intersect each other follow, is limited and so described in its geometry.

In the context of the present invention, the profile function is, for example, the power function h = ε · x ⁿ , with different ones in this case ε _i and n _i , or also different edge thicknesses h _{0, i} are.

The circumferential coordinate u is precisely that curve on the surface of the acoustic black hole on which every x coordinate of a profile function describing the geometry of an acoustic black hole has exactly the value x _{u, i} , for which hi (x> x _{u, i} ) = d = const. applies, i.e. the curve that limits the area of maximum thickness of the acoustic black hole.

In a further preferred embodiment of the device according to the invention, the at least one acoustic black hole is 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 attached to modal oscillation maxima in the interior of the device.

In the context of the present invention, the modal oscillation maxima are those points at which the flexural oscillation of the selected mode has the greatest amplitudes in terms of oscillation path, oscillation velocity and oscillation acceleration.

With this embodiment, acoustically important natural bending modes of the cover or base plate or of a component of the device according to the invention in which it is used can be attenuated. A device according to the invention is also preferred in which the at least one acoustic black hole 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 Part of the frame 115 the device is.

The advantage of this embodiment is that weight can be saved as a result and the length of the acoustic black hole 1 _ASL becomes greater, as a result of which lower frequencies can be attenuated.

A device according to the invention is particularly preferred in which the at least two outer components 10 , 14th , 15th , 18th , 20th , 22nd , 25th at least one acoustic black hole 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 or an acoustic black hole 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 and at least two connectors 60 , 61 are coupled to each other.

In the context of the present invention, an acoustic black hole can itself represent a connecting piece.

The advantage of this embodiment of the device according to the invention is that it increases the rigidity of the entire device and the vibrations of both sound-emitting sides are coupled into the acoustic black holes.

The connecting pieces preferably consist of a thermally insulating material, for example a ceramic. This can make it possible to use a thermally less resilient material of the acoustic black holes if the device according to the invention with contact to the connector assumes higher temperatures in the application, and if the damping material also has thermally insulating properties. The connection can be created in different ways. Firstly, a screw connection can be established between the paneling parts, which the at least one acoustic black hole provided with a through-hole and the connecting pieces non-positively and / or positively between the outer components, e.g. B. cover and base plate, clamped, the bracing by a nut outside the outer components or by a threaded hole into which a connecting screw is screwed, takes place. The form-fitting connection is ideal for the following special design: The connecting pieces can also consist of an elastomer or, for thermally demanding applications, a wire mesh buffer that elastically couples the acoustic black hole to the top and bottom plate. The acoustic black hole could also function as the mass of a mass-damper-spring system, which, if properly tuned, can dampen a certain and also low-frequency natural structural frequency. The connecting pieces represent a spring and a damper at the same time. Furthermore, riveting can also be attached, with a rivet is used instead of the connecting screw and the holes in the outer components are adapted to this connecting element. In addition, with similar materials, a cohesive connection can be established between the at least one acoustic black hole and the outer component, and also, on the other hand, between the acoustic black hole and the connecting piece. The friction welding process, for example, is ideal here. This creates a connection between an outer component, in particular a base plate, the at least one acoustic black hole and the acoustic black hole and a connecting piece by means of melting zones. However, it is also possible to have a threaded hole in the connecting piece, via which the connecting piece is braced against the outer component, preferably the cover plate, with a short screw. Thirdly, as other material connections, soldered or glued connections can also be produced at the same positions if the intended use of the structure of the acoustic black holes takes place at temperatures that are below the softening temperature of the respective connection material used.

The at least one acoustic black hole preferably comprises a bore with a larger inner diameter than the outer diameter of the connecting pieces, so that the connecting piece cannot spatially overlap with the acoustic black hole. Not only a simple drilling is conceivable here, but such a design of the edge of the borehole is conceivable in which it itself has the shape of a small acoustic black hole, i.e. the sheet thickness steadily decreases towards the edge of the hole, in the simplest case in the form of a sharp edge of the hole , linear, optimally flat bevel.

The at least one acoustic black hole is preferably fastened on one side either to the cover or base plate or to the main sheet and support sheet or to the inner shell and outer shell by means of a connecting piece.

In the context of the present invention, the fastening can be via screws 52 , 80 , Threaded holes 12 and nuts 53 take place or by means of a friction weld, solder or adhesive connection 41 , 75 .

A device according to the invention is particularly preferred in which at least two acoustic black holes 40 , 45 , 47 , 48 , 50 , 55 , 57 , 58 are fastened to one another in the areas of their greatest thickness and are arranged one above the other in such a way that they form a stack.

The advantage of this embodiment is that the connecting piece can be shorter or even omitted. Accordingly, nut (s) for the connecting screw (s) can also be omitted and the stack produced by the arrangement can be made through a thread in the last acoustic black hole.

Particularly preferred is a device according to the invention in which the device continues to support ( 90 ' , 90 " , 90 "' ) includes.

In the context of the present invention, supports are support bodies, surfaces for supporting components made of plastic or metal. These supports are divided into k + 1 layers according to the number k of acoustic black holes supported by them. The supports are to be positioned in the room so that they cannot move so that the minimally thin edge of the acoustic black hole protrudes over the support by at least a third of the length of the acoustic black hole.

Furthermore, the object of the present invention is achieved by a device for absorbing forces, transmitting and damping mechanical vibrations in a bearing, which has at least one acoustic black hole 49 ' , 49 " , 49 " ', 59 ' , 59 " , 59 "' on the device side 49 and / or on the support side 59 includes, which in its area of maximum thickness or maximum and high thickness by a bearing elastomer 95 with at least one acoustic black hole 49 ' , 49 " , 49 " ', 59 ' , 59 " , 59 "' or a plate 62 on the other hand, one perpendicular to the at least one acoustic black hole 49 ' , 49 " , 49 '" , 59 ' , 59 " , 59 "' or the plate 62 acting bearing force, which is caused by a device mount 29 recorded and a support recording 19th is emitted, completely over the high thickness area of the at least one acoustic black hole 49 ' , 49 " , 49 " ', 59 ' , 59 " , 59 "' and completely through the bearing elastomer 95 is transferred and at least one damping bearing material 31 , 32 , which is the at least one acoustic black hole 49 ' , 49 " , 49 " ', 59 ' , 59 " , 59 "' encloses at least in its area of minimal thickness.
The at least one acoustic black hole preferably decreases in thickness towards the outside or inside.
Furthermore, the at least one acoustic black hole preferably has the bearing elastomer in its area of maximum thickness or maximum and high thickness.
In the sense of the present invention, the device side is the side of the bearing on which the object supported by the bearing transfers its weight or another force transmitted or generated by it to the bearing, which is caused by the Stock is recorded and transferred. The support side, on the other hand, is the side in which the force absorbed on the device side, cleared of vibrations by the effect of the bearing, is introduced into a solid body to which the bearing is mechanically connected by the support mount and which can be viewed as solid ground becomes.
The at least one acoustic black hole is preferably flat, curved in a rotationally symmetrical manner or curved in a rotationally symmetrical manner in a spiral shape.

The advantage of connecting the at least one black hole at its greatest thickness to the outer components is that vibrations can be transmitted in this way.
The advantage of the arrangement of the at least one damping material, which encloses the at least one acoustic black hole at least in its area of minimal thickness, is that it absorbs and dissipates the vibrations of the at least one acoustic black hole.
In a preferred embodiment of the device according to the invention, there are at least two acoustic black holes on at least one of the bearing sides 49 ' , 49 " , 49 " ', 59 ' , 59 " , 59 "' fastened to one another in the areas of their greatest thickness and arranged one above the other in such a way that they form a stack and at their thin areas of at least one damping bearing material 31 , 32 are enclosed.
The advantage of this embodiment is that, through the formation of stacks, the bearing force of the acoustic black holes is equally transmitted.
Furthermore, a device according to the invention is preferred in which the device receptacle 29 Drilled throughout in the direction of the bearing force and the support mount 19th countersunk is drilled and both holes via a matching bolt 65 are connected, which is the bearing elastomer 95 penetrates and lateral forces from the device mount 29 on the support mount 19th transmits.
A device according to the invention which has a bearing frame is particularly preferred 118 having the at least one damping bearing material 31 , 32 and that at least one acoustic black hole 49 ' , 49 " , 49 " ', 59 ' , 59 " , 59 "' surrounds.
The advantage of a bearing frame is that it protects both the at least one damping bearing material and the at least one acoustic black hole from external influences without hindering a displacement of the bearing halves with respect to one another under the action of force.
In addition, a device according to the invention is preferred in which the at least one damping bearing material ( 31 , 32 ) for at least one acoustic black hole ( 49 ' , 49 " , 49 " ', 59 ' , 59 " , 59 "' ) is available separately on each of the storage sides.
Furthermore, in the context of the present invention, the at least one damping material can be further subdivided.
The device according to the invention can be used where at the same time compressive forces normal to the plate or shell plane are to be absorbed and / or transmitted, or tensile and compressive loads in the direction of the plane, with the structure in particular vibrations in the audio frequency range from 16 Hz to 20 kHz should dampen. A distinction is made between the one application in which the force is transmitted from one component via the structure to another component, and the vibration in the audio frequency range is partially or completely dissipated in the structure, and that in which the structure is converted into a wall-shaped part is integrated or replaces it, which absorbs structure-borne and / or air-borne sound, forwards it and emits air-borne sound elsewhere as audible, annoying or otherwise undesirable. In both cases, the mode of operation of the invention is that a flat or curved acoustic black hole is built into the structure in such a way that some of the vibrations introduced into it enter the acoustic black hole, continue therein as a bending vibration, and in the area of the The smallest thickness of the acoustic black hole ideally reaches a speed of propagation of zero, i.e. does not run back, but generates a large oscillation amplitude in this area, which is absorbed directly by a damping material that is enclosed within the structure and the acoustic black hole at least in its area “Tip” surrounds it so that the vibration energy is dissipated by it, i.e. converted into heat and not transferred to the adjacent component or the adjacent air. The device according to the invention is therefore suitable for the low-noise display of housing parts of sound-emitting power and working machines, household appliances, parts of the vehicle body. As a passive vibration-reducing support bearing for machines, it can prevent or reduce the introduction of structure-borne noise that is perceived as disturbing elsewhere and thus contribute to improving the comfort of use. In principle, it is also suitable for use as impact sound insulation in buildings. Since all essential components of the device according to the invention can be made from both heat-resistant materials and lightweight composite materials, it can also be used under difficult thermal conditions and when lightweight construction is required.

Preferably, the properties of acoustic black holes are used to absorb the vibrations of a plate or shell and to focus on an area where they are amplified by amplifying the vibration amplitudes can be effectively converted into heat with little use of damping material. Due to the possibility of producing acoustic black holes as thin and light parts, the design of the original plate or shell into the device according to the invention can be carried out with a small increase in mass and thickness. The risk of the panel material tearing when a force is applied, which occurs when an acoustic black hole is directly introduced into a panel, is avoided by arranging the thin area of the acoustic black hole in such a way that the flow of force through it is minimal.

In the case of an application with an already given integral arrangement of dampening material, such as in double-walled body parts, the concept can also be represented without increasing the thickness and an externally invisible integration of the acoustic black hole is possible.

The concept can also enable weight savings, for example, if the structural vibration damping means that a heavy and stiffer structure can be dispensed with, for example in the case of an aluminum oil pan, which can be replaced by a lightweight plastic construction with plastic foam and an integrated acoustic black hole.
The at least one acoustic black hole can be arranged in the device according to the invention in such a way that its area of maximum thickness can transmit compressive and tensile forces and increase the overall rigidity of the structure.

Furthermore, the device according to the invention comprises electrically controllable and actively vibration-reducing actuators. These can be attached both to moderately thick areas of the at least one acoustic black hole and in the interior or on the outer surface of the device according to the invention. The sensors and regulators known to those skilled in the art, which are also necessary for active damping, are also included in the device according to the invention if they are used to detect the vibration state of the device according to the invention and to control the actuators mounted on or in it. Piezo patches can be used as such, but they can also serve to record structure-borne noise stresses. The combination of an actuator layer with a viscoelastic one is what is known as Active Constrained Layer Damping (ACLD). In order to cancel the vibrations, the controllable layer must be made to vibrate by the controller in such a way that it has a phase offset of about 180 ° to the previously metrologically recorded incoming unwanted sound vibrations and thus cancels them out through destructive interference. Such active vibration damping methods can in principle only dampen low-frequency vibrations up to approx. 200 Hz and are therefore suitable for supplementing, but not replacing, the action of the passively acting ABH structures according to the invention.

Most of the components of the present device are simple semi-finished products or standard parts, the manufacture of which is known to the person skilled in the art and therefore does not require any more detailed explanation. The outer components are basically flat shapes, in particular those with continuous holes of any shape within the main surface of the outer component, which also represent an edge of this surface and, like the outer edges of the surface, must be designed in such a way that the damping material cannot escape is, and the protection of the same from external influences is just as good as at the outer edge areas. Here, too, contact with the thin edges of the at least one acoustic black hole must be ruled out by design.

The production of acoustic black holes, on the other hand, is a manufacturing challenge, which is used by known production methods such as milling, in particular for most simple acoustic black holes, but is not suitable for mass production or the production of complex, shell-shaped acoustic black holes. Furthermore, casting, drop forging and vacuum lamination are processes which are also suitable for the production of the more complex shell-shaped acoustic black holes according to the invention. Further possible manufacturing processes are (1) deep-drawing, which must be done with a slightly and precisely conically shaped punch which, in the process of lowering, pulls the sheet to be formed into a gap between punch and die that is increasingly smaller according to the profile function, which tends to zero and there leads to material demolition, (2) the rapid prototyping process for research purposes with rather smaller dimensions but complex geometries, (3) prepreg lamination processes in which the edge thickness h ₀ is predetermined by the height of the individual fiber mats and the thickness profile of the acoustic blacks Holes can be specified by cutting the length of these fiber mats, (4) the electrical discharge machining of sheet metal, (5) precise grinding from the solid for flat and curved acoustic black holes and (6) the grinding of material edges created in other ways to additionally reduce the minimum thickness and to generate advantageous fraying Margins.

Advantageous further developments of the invention emerge from the patent claims Description and the drawings. The advantages of features mentioned in the description and the combinations of several features are only exemplary and can come into effect alternatively or cumulatively without the advantages necessarily having to be achieved by embodiments according to the invention.

Further features can be found in the figures - in particular the illustrated geometries and the relative dimensions of several components to one another and their relative arrangement and operative connection. The combination of features of different embodiments of the invention or of features of different patent claims is also possible, deviating from the selected back-references of the patent claims, and is hereby suggested. This also applies to features that are shown in separate figures or mentioned in their description. These features can also be combined with features of different patent claims. Features listed in the claims for further embodiments of the invention can also be omitted.

The number of features mentioned in the claims and the description are to be understood in such a way that precisely this number or a greater number than the specified number is present without the need for the explicit use of the adverb “at least”. So if, for example, one ABH is mentioned, this is to be understood in such a way that there is exactly one ABH, two ABH or more ABH. These characteristics can be supplemented by other characteristics or be the only characteristics that make up the product in question.

• 1 das erfindungsgemäße Merkmal eines plattenförmigen Akustischen Schwarzen Loches darstellend die in der Beschreibung aufgeführten Parameter zur Beschreibung über der Umfangskoordinate u variabler Profilgeometrien;
• 2 eine schematische Ansicht der erfindungsgemäßen Vorrichtung in ebener Form;
• 2a eine schematische Ansicht der erfindungsgemäßen Vorrichtung mit erfindungsgemäßen Merkmalen ihrer Gestaltung als Lager;
• 2b eine schematische der erfindungsgemäßen Vorrichtung mit erfindungsgemäßen Merkmalen ihrer Gestaltung als Lager unterschieden von der ersten durch die Verwendung einer Platte anstelle eines Stapels aus Akustischen Schwarzen Löchern;
• 3 eine schematische Ansicht einer dritten Ausführungsform der erfindungsgemäßen Vorrichtung unterschieden von der ersten durch die Erfindungsmerkmale Form und Montage der Akustischen Schwarzen Löcher;
• 4 eine schematische Ansicht einer vierten Ausführungsform der erfindungsgemäßen Vorrichtung unterschieden von der ersten durch die Form und Montage sowie Anordnung des dämpfenden Materials sowie Auflager;
• 5 eine schematische Ansicht einer fünften Ausführungsform der erfindungsgemäßen Vorrichtung mit dem erfindungsgemäßen Merkmal einer blechförmigen Ausprägung der äußeren Teile;
• 6 eine schematische Ansicht der in 5 gezeigten Ausführungsform mit zusätzlichen akustischen Gestaltungsmerkmalen sowie einem vollständig geschlossenen Aufbau;
• 7 einen Längsschnitt einer ersten Ausführungsform eines Schalenaufbaus der Struktur eines Akustischen Schwarzen Loches am Beispiel einer Ölwanne.
• 8 einen Längsschnitt einer zweiten Ausführungsform eines Schalenaufbaus der Struktur eines Akustischen Schwarzen Loches am Beispiel einer Ölwanne.

In the following, the invention will be further explained and described using the exemplary embodiments shown in the figures. It shows

• 1 the inventive feature of a plate-shaped acoustic black hole representing the parameters listed in the description for the description of the circumferential coordinate u of variable profile geometries;
• 2 a schematic view of the device according to the invention in planar form;
• 2a a schematic view of the device according to the invention with inventive features of its design as a bearing;
• 2 B a schematic of the inventive device with inventive features of its design as a bearing differentiated from the first by the use of a plate instead of a stack of acoustic black holes;
• 3 a schematic view of a third embodiment of the device according to the invention differentiated from the first by the inventive features of the shape and assembly of the acoustic black holes;
• 4th a schematic view of a fourth embodiment of the device according to the invention differentiated from the first by the shape and assembly and arrangement of the damping material and supports;
• 5 a schematic view of a fifth embodiment of the device according to the invention with the inventive feature of a sheet-like expression of the outer parts;
• 6th a schematic view of the in 5 embodiment shown with additional acoustic design features and a completely closed structure;
• 7th a longitudinal section of a first embodiment of a shell structure of the structure of an acoustic black hole using the example of an oil pan.
• 8th a longitudinal section of a second embodiment of a shell structure of the structure of an acoustic black hole using the example of an oil pan.

1 shows the geometry describing profile functions h (x) of a flat acoustic black hole, which over a circumferential coordinate u or different x-axes x _i x _{i + 1} , ..., x _{i + n} different coefficients ε, n, γ, m, ... of h (x) and different edge thicknesses h ₀ . This means that the profile length of the acoustic black hole l _ASL can also vary over u. Based 8th one can imagine curved x-axes, thus curved acoustic black holes.

2 shows a flat, frame-supported structure of the device according to the invention with an integrated frame, the device according to the invention being designed as a plate with a constant thickness. The device according to the invention comprises a base plate as external components 10 and a cover plate 20th . The bottom plate 10 is designed so that it has a frame-like expression that forms the frame of the plate, which is approximately orthogonal to the plate plane, and with the cover plate 20th connected is. In the case of plastic injection molding or the laminating production of a composite material, the frame-like expression can be produced by primary molding; in the case of a metal design made from thin-walled sheet metal, deep-drawing is also an option as a forming process in addition to casting. If the frame has a sufficient width, one can be made in the molding process or A recess created subsequently, for example by milling 11 the recording of the cover plate 20th serve.

In 3 a second embodiment of the device according to the invention is shown. In this embodiment, the device according to the invention is a flat, frame-supported structure with an independent frame 115 , which with base plate 10 and cover plate 20th is connected by a material connection or another type of connection.

4th shows a structure similar to 2 . In contrast to the 2 , is in 4th shown that the top panel 20th itself can also have a frame-like expression. With such a structure, the frame must 115 through matching cutouts for the one in the frame 115 at least one acoustic black hole to be integrated 48 , 58 be provided. For the purposes of the present invention, several acoustic black holes can also be used 48 , 58 as part of 115 be integrated.

In the 5 The embodiment shown of the device according to the invention manages almost without a frame. It is a quasi-flat shell structure that takes up a curved sheet metal section of a vehicle floor panel with a damping effect, which is in the form of the curved skin sheet 22nd present and with a support plate 18th , which can also be arched, is connected, so that also a cavity for the damping material 30th arises. In the case of a marginal attachment of the at least one acoustic black hole 48 , 58 can seal the free edges 110 , 110 ' made of elastomer, closed-cell plastic foam or soft metal. The quasi-flat shell structure of the device according to the invention according to the present embodiment can, however, also have an acoustic black hole that is not mounted at the edge, but with at least one internally mounted acoustic black hole 48 , 58 be provided. In the present embodiment, the support plate is used 18th excluding the absorption of the damping material 30th and ends at the edges of the cavity.

In 6th the embodiment of the device according to the invention is according to 5 shown, whereas the support plate 18th in this embodiment continues to the left and right of the cavity area, and there for example by gluing to the main sheet 22nd is connected, and here additionally takes on supporting, force-guiding functions. The bond can be designed in such a way that the area also has damping properties.

7th and 8th show a fifth embodiment of the device according to the invention, which has a non-planar, arbitrarily angular, convex, concave shell structure. These embodiments are illustrated using the example of a typical oil pan geometry with an inner shell 25th and an outer shell 14th shown. In 7th it is shown that the at least one acoustic black hole, which is also in the form of a shell, is accommodated near the edge, whereas it is in the 8th is recorded at the edge.

In the 2 and 3 it is also shown that there is at least one acoustic black hole 40 , 45 , 48 , 50 , 55 , 58 at the edge of the outer components 10 , 14th , 18th , 20th 22nd or can be mounted centrally. Mounting at the oscillation maxima of acoustically dominating bending modes of the device according to the invention will particularly dampen these modes; the acoustic black holes are exemplary 50 , 55 arranged at the maxima of the 2.2 bending modes of the device according to the invention, and the larger acoustic black holes 40 , 45 at the maximum of the 1.1 bending mode. In the 2 Assembly of the acoustic black holes shown 40 , 50 between top and bottom plate 20th , 10 sets using the connectors 60 , 61 a stiffening of the device according to the invention, that is, a shift of corresponding modes to higher frequencies and their attenuation in relation to higher, non-blocked modes. This is advantageous as the damping effect of the damping material 30th usually increases with higher oscillation frequency. If, on the other hand, a rather soft panel design is required, as could be the case, for example, in applications for footfall insulation, a structure without stiffening connecting elements can be used, as in 3 shown. The 2 and 3 furthermore show various mounting options for the at least one acoustic black hole 40 , 45 , 50 , 55 as well as the load-bearing parts of the external components 10 , 20th , 115 . The at least one acoustic black hole 40 , 45 , 50 , 55 is partly through a material connection 12 , 41 , 52 , 53 , 75 , 80 such as surface friction welding, or gluing or soldering, fixed or screwed. Also show the 2 and 3 a two- and three-part design of the load-bearing outer components 10 , 20th , 115 . In both figures, a cohesive assembly is shown, while in 4th and 5 Form-fitting types of assembly using screws 80 or rivet 100 to be illustrated. In the three-part design of 3 the frame is present as a special part, while in 2 an expression of the base plate 10 which in this case must be produced in a primary or reshaping process. According to the embodiment of the device according to the invention in 4th there must also be suitable indentations in the Frame features are introduced where the at least one acoustic black hole mounted on the edge 48 , 58 attached as part of the frame. The ones in the 4th to 8th The illustrated arrangement of the at least one acoustic black hole 47 , 48 , 57 , 58 at the edge of the device according to the invention is particularly useful in applications where the introduction of force takes place at these edges and the plate or shell surface amplifies these vibrations and transmits them as sound to the fluid environment. An introduction of force at the edge takes place, for example, when the structure is installed on a frame which absorbs and transmits forces and / or vibrations. The cylinder crankcase of an internal combustion engine, for example, can be understood as such. Since the oil pan is mounted on this cylinder crankcase and placed over the flange surface, an edge area that introduces vibrations 7th and 8th Appropriate installation positions close to the edge of the shell-shaped, unilateral acoustic holes 47 , 57 A peripheral assembly of the acoustic black holes 47 , 57 is also particularly suitable for frame-mounted, sheet-like cladding parts: starting with shielding sheets for the exhaust gas aftertreatment system, through sound-conducting and radiating parts of various vehicle bodies, right up to equipment cladding in the catering and household sectors. Examples of such applications are 5 and 6th with a riveted assembly of slightly curved acoustic black holes tapering on one side 48 , 58 in a non-rectangular frame. The embodiment of the device according to the invention looks according to 5 as an alternative to a frame part seals 110 , 110 ' in the edge areas. However, these are unnecessary if the support plate 18th , as in 6th shown, the entire main sheet flat 22nd covered and not only, as in 5 who have favourited Acoustic Black Hole and Damping Material Chambers. Support plate 18th and main sheet 22nd can be made as thin as possible for weight reasons, especially the support plate 18th only requires a thickness of one or a few tenths of a millimeter (n) due to its only material-bearing function. In the embodiment of the device according to the invention according to 6th are with beads 120 and ribs 130 further possible designs indicated, as well as additional external acoustic insulation 140 including protective or heavy layer 150 . While in 6th the shape of the ribs 130 can be generated by forming manufacturing processes, are in the embodiments of the devices according to the invention that are in the 7th and 8th are shown, originally forming, for example in aluminum or plastic casting, or in the lamination process, stiffening ribs to be produced 135 shown.

In the in 2 shown embodiment of the device according to the invention is with the connector 60 , 61 the acoustic black holes 40 , 50 against the cover plate 20th and base plate 10 the possibility of power transmission through the areas of acoustic black holes 40 , 50 given with maximum thickness. This aspect of the plate and shell-shaped self-damping structures is used in the design of the device according to the invention as a self-damping bearing. The scheme of such a camp is given in 2a) and 2 B) shown. Unlike the plate and shell designs, it sees some complete power and thus also vibration conduction through at least one acoustic black hole on the side of the device 49 ' , 49 " , 49 " ', which has a bearing elastomer 95 with a plate 62 or another acoustic black hole 59 ' , 59 " , 59 "' is connected on the support side of the bearing. On both sides, as in the 1a shown stacks, each consisting of several acoustic black holes 49 ' , 49 " , 49 '" , 59 ' , 59 " , 59 "' existing. That or the acoustic black holes 49 ' , 49 " , 49 " 'on the device and / or support side absorb the vibrations and focus them with low reflection to their thin edges, where they are absorbed by the damping bearing material 31 , 32 be dissipated. In contrast, the areas of high thickness of the acoustic black hole (s) on the side of the device create little dynamic forces 49 ' , 49 " , 49 '" , the bearing elastomer 95 , and if necessary the plate 62 or the acoustic black holes 59 ' , 59 " , 59 "' forwarded to the support page. The frame 115 the device according to the invention in 3 is in a storage frame 118 transformed, which however according to the present inventive device does not absorb and transmit functional forces, but the fixation of the damping bearing materials 31 , 32 serves. In 2a) are for the acoustic black holes on the device side 49 ' , 49 " , 49 " 'and for the acoustic black holes of the support side 59 ' , 59 " , 59 "' two separate cushioning storage materials 31 , 32 provided, which in turn consist of four circular ring sections for assembly reasons. The separation of the upper and lower cushioning material 31 , 32 prevents particularly with larger oscillation amplitudes and dynamic shifts of the at least one acoustic black hole on the device side 49 ' , 49 " , 49 " against the plate or the acoustic black holes on the support side 59 ' , 59 " , 59 "' an occurrence of bending forces at the thin edges of the acoustic black holes or the acoustic black hole 49 ' and the plate 62 on both sides of the bearing elastomer 95 , which separates the device and support side, as a result of compression not only of the bearing elastomer, but also a possible unitary block of damping bearing material 31 , 32 . The bearing is used to absorb forces along the Axis of device support 29 and support mount 19th Act. By connecting the two with a bolt 65 , which for example with a press fit in the support seat 19th was introduced, and in a fine, possibly greased clearance fit in a hole in the device mount 29 running, transverse and bending forces can also be absorbed, and undesired vibrations of the same can be transmitted into the acoustic black holes. The design of the plate 62 as a simultaneous inclusion of the bearing elastomer 95 in 2 B) also enables lateral forces to be absorbed.
The frame 115 the device according to the invention in 3 is in a storage frame 118 transformed, which however according to the present inventive device does not absorb and transmit functional forces, but the fixation of the damping bearing materials 31 , 32 serves.

Further acoustically effective configurations are deep-drawn ribs or ribs produced by other deformation 130 and beads 120 . For example, ribs produced in plastic injection molding (also: surface fine ribbing, e.g. honeycombs), such as those in 7th and 8th shown stiffening ribs 135 the inner shell 25th the oil pan, additionally applied / glued-on insulation layer 140 from an acoustically effective cohesive material such. B. polyurethane foam, as in 6th or, fourthly, an additional heavy and / or protective layer 150 , as in 6th shown by combining with the insulating material 140 A mass-damper-spring system is created as a mass layer, which brings about additional, specifically designed noise reduction effects. Pores or holes, which have a sound-reducing effect, can also be made in this heavy layer.

• Die beschriebene vorliegende Erfindung beschreibt eine Vorrichtung zur Kontaktaufnahme und Weiterleitung statischer oder niedrigfrequenter Kräfte, welche eine gegebene Platten- oder Schalenstruktur, die unzweckmäßiger Weise Schwingungen überträgt und/oder unerwünschter Weise als Schall abstrahlt, ersetzt durch einen äußerlich platten- oder schalenförmigen Aufbau mit mindestens vier funktionalen Komponenten, welcher eine Fokussierung der Schwingungen im inneren des Aufbaus forciert und begünstigt und dort für eine Verwandlung der Schwingungen in Wärme (Dissipation) sorgt. Ein solcher Aufbau zeichnet sich durch vielfältige Anwendungsmöglichkeiten aus. Er kann verkleidende Platten oder Bleche von Maschinen ersetzen und so zu einer Verringerung des von der Maschine abgestrahlten Schalles und zur thermischen Isolation beitragen. Er lässt sich als schwingungsdämpfendes Auflager für vibrierende Aggregate wie Hubkolben-Verbrennungsmotoren einsetzen, dessen Wirkung durch Mehrfachschichtung oder -Anordnung verstärkt werden kann. Er eignet sich aufgrund seiner Plattenform zur Trittschalldämmung in Gebäuden und ermöglicht die Beruhigung von PKW-Karosserien, in welche er funktional und mittragender Funktion integriert werden kann. Im Haushaltsbereich können beispielsweise Geräte, die durch Oberflächenschwingungen störenden Lärm emittieren, wie z. B. Waschmaschinen oder Kaffeeautomaten durch entsprechend gestaltete Außenverkleidungen beruhigt werden. Das vorgestellte Prinzip kann auch in komplexer geformten schwingenden Teilen Anwendung finden, wie z. B. bei der Gestaltung akustisch besonders kritischer Ölwannen von PKW- oder LKW-Verbrennungsmotoren. Auch Anwendungen bei hohen Betriebstemperaturen, wie in Heißgassystemen sind nach den Erfindungsansprüchen möglich. Aufgrund der vielfältigen Anwendungsgebiete beschränkt sich die Darstellung des Standes der Technik auf das angewandte Prinzip und auf einige passiv selbstdämpfende Systeme aus dem Automobil-Bereich.

The present invention is summarized again in other words below:

• The present invention described describes a device for establishing contact and forwarding static or low-frequency forces, which replaces a given plate or shell structure that inexpediently transmits vibrations and / or undesirably radiates as sound, replaced by an externally plate or shell-shaped structure with at least four functional components, which forces and favors a focusing of the vibrations inside the structure and ensures that the vibrations are transformed into heat (dissipation). Such a structure is characterized by a wide range of possible applications. It can replace cladding panels or sheet metal on machines and thus contribute to a reduction in the noise emitted by the machine and to thermal insulation. It can be used as a vibration-damping support for vibrating units such as reciprocating internal combustion engines, the effect of which can be reinforced by multiple layers or arrangements. Due to its panel shape, it is suitable for footfall sound insulation in buildings and enables car bodies to be calmed, into which it can be integrated in a functional and supporting role. In the household sector, for example, devices that emit disturbing noise due to surface vibrations, such as B. washing machines or coffee machines can be calmed by appropriately designed exterior panels. The principle presented can also be used in vibrating parts with a more complex shape, such as B. in the design of acoustically particularly critical oil pans in car or truck internal combustion engines. Applications at high operating temperatures, such as in hot gas systems, are also possible according to the claims of the invention. Due to the diverse areas of application, the presentation of the state of the art is limited to the principle used and to some passive self-damping systems from the automotive sector.

List of reference symbols

10

Base plate

11

deepening

12

Threaded hole

14th

Outer shell

18th

Support plate

19th

Support mount

20th

Cover plate

22nd

Main sheet

25th

Inner shell

29

Device recording

30th

cushioning material

31, 32

cushioning storage material

40, 45, 47, 48, 50, 55, 57, 58

Acoustic black hole

41, 75

Friction welded, soldered or glued connections

49 ', 49 ", 49"'

Acoustic black hole on the device side

52, 80

screw

53

mother

59 ', 59 ", 59"'

Acoustic black hole support side

60, 61

Connector

62

plate

65

bolt

90, 90 ', 90 ", 90"'

In stock

90 '

Support position 1

90 "

Support layer 2

90 "'

Support position 3

95

Bearing elastomer

100

Rivet

110, 110 '

Seals

115

frame

118

Storage frame

120

Beads

130

Ribs

135

Stiffening ribs

140

Insulation layer

150

Heavy and / or protective layer

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 2013/0071251 A1 [0003]
• DE 102015100442 A1 [0003]
• DE 102016116554 B3 [0003]
• CN 106023979 A [0003]
• US 2018/0335406 A1 [0003]
• EP 0245636 B1 [0004]
• DE 102012022935 A1 [0004]
• DE 102006004432 A1 [0004]

Non-patent literature cited

• M. A. Mironov ("Propagation of a flexural wave in a plate whose thickness decreases smoothly to zero in a finite interval"; Soviet Physics - Acoustics; Vol. 34 (1988); pp. 318-319) [0002]
• V. V. Krylov, ("Acoustic, black holes' for flexural waves and their potential applications"; Proceedings of the Institute of Acoustics Spring Conference; Salford, UK, 25-27 March 2002) [0002]
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Claims (17)

Device for absorbing force, transmitting and damping mechanical vibrations, comprising at least two outer, interconnected components made of coherent materials (10, 14, 18, 20, 22, 25), which together form a closed cavity which is at least partially covered with damping material (30) is filled, which encloses at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) in the region of its smallest thickness, and in the region of its maximum thickness with at least one of the two outer components (10, 14, 18, 20, 22, 25) is firmly connected. Device according to Claim 1 , characterized in that the device further comprises a frame (115), which together with the outer components (10, 14, 18, 20, 22, 25) forms the closed cavity. Device according to one of the Claims 1 or 2 , characterized in that the at least two outer components (10, 14, 18, 20, 22, 25) are sheet-metal, plate-shaped or shell-shaped. Device according to one of the preceding claims, characterized in that the cohesive material is selected from the group consisting of metal, plastic and composite material. Device according to one of the preceding claims, characterized in that the damping material (30) has a loss factor of η> 0.05. Device according to one of the preceding claims, characterized in that the at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) has a geometry which, starting from an inner surface, radiates to all edges decreases towards the minimum thickness achievable in terms of production technology. Device according to Claim 6 , characterized in that the at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) over the circumferential coordinate different, continuously or also discontinuously changing coefficients of the geometry of the at least one acoustic black hole ( 40, 45, 47, 48, 50, 55, 57, 58) assumes the predefined profile function. Device according to one of the Claims 1 to 7th , characterized in that the at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) is attached to modal oscillation maxima in the interior of the device. Device according to one of the Claims 1 to 7th , characterized in that the at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) is part of the frame (115) of the device. Device according to Claim 9 , characterized in that the at least two outer components (10, 14, 15, 18, 20, 22, 25) over at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) or over at least one acoustic black hole (40, 45, 47, 48, 50, 55, 57, 58) and two connecting pieces (60, 61) are coupled to one another. Device according to Claims 1 to 10 , characterized in that at least two acoustic black holes (40, 45, 47, 48, 50, 55, 57, 58) are attached to one another in the areas of their greatest thickness and are arranged one above the other in such a way that they form a stack. Device according to one of the preceding claims, characterized in that the device further comprises supports (90 ', 90 ", 90"'). Device for absorbing force, transmitting and damping mechanical vibrations in a bearing comprising at least one acoustic black hole (49 ', 49 ", 49'", 59 ', 59 ", 59"') on the device side (49) and / or on the Support side (59), which by a bearing elastomer (95) with the at least one acoustic black hole (49 ', 49 ", 49'", 59 ', 59 ", 59"') or a plate (62) on the other side is supported, a bearing force acting perpendicular to the at least one acoustic black hole (49 ', 49 ", 49'", 59 ', 59 ", 59"') or the plate (62), which is caused by a device mount (29) and a support receptacle (19) is released, completely over the area of high thickness of the at least one acoustic black hole (49 ', 49 ", 49"', 59 ', 59 ", 59"') and completely through the bearing elastomer (95 ) is transferred and at least one damping bearing material (31, 32), which the at least one acoustic black hole (49 ', 49 ", 49"', 59 ', 59 ", 59"') at least mostly encloses in its area of minimal thickness. Device according to Claim 13 , characterized in that at least two acoustic black holes (49 ', 49 ", 49'", 59 ', 59 ", 59"') are attached to one another in the areas of their greatest thickness and are arranged one above the other on at least one of the bearing sides, that they form a stack and are enclosed in their thin areas by at least one damping bearing material (31, 32). Device according to Claim 13 or 14th , characterized in that the device receptacle (29) is drilled continuously in the direction of the bearing force and the support receptacle (19) is drilled with a countersunk hole and both bores are connected via a suitable bolt (65) which penetrates the bearing elastomer (95) and transverse forces from the device receptacle (29 ) transfers to the support receptacle (19). Device according to one of the Claims 13 to 15th , characterized in that a bearing frame (118) surrounds the at least one damping bearing material (31, 32) and the at least one acoustic black hole (49 ', 49 ", 49"', 59 ', 59 ", 59"'). Device according to one of the Claims 13 to 16 , characterized in that at least one damping bearing material (31, 32) for at least one acoustic black hole (49 ', 49 ", 49"', 59 ', 59 ", 59"') is present separately on each of the bearing sides.

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